Nearest Stops

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations exist, so the description carries the full burden. It does usefully disclose the per-result payload (walk minutes, routes, directions, headsigns, active disruptions) and implies a proximity-ordered read, but says nothing about empty-result behavior, radius-outside behavior, rate limits, or auth, which matter for a live transit API.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

One dense sentence, front-loaded with the core action and with the geocoding caveat in parens where it's scannable. Slightly run-on at the tail enumerating return fields, but no dead weight.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values needn't be explained, and the description covers purpose plus ranking input. But for a five-parameter tool with zero schema documentation and no annotations, the absence of any mention of radius, limit, or kind filtering leaves the agent guessing how to tune the search.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% across five parameters. The description only implies lat/lon and loosely gestures at `kind` via 'stops and stations'; it never explains `radius_m` (default 500), `limit` (default 10), or how `kind` filters results — the three parameters most likely to be mis-set.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource with scope: stops and stations nearest a coordinate. That proximity framing is distinct from the name-oriented siblings (find_stops, stop, station) and lets an agent pick it without opening schemas, but it never names those siblings explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives a real precondition — geocode addresses with a maps tool first — which prevents a whole class of failed calls. It stops short of stating exclusions or naming find_stops as the alternative for name-based lookup, so it's clear context rather than full when/when-not guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.